The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 18, 1989
Filed:
Jan. 30, 1987
Masaharu Kobayashi, Yokohama, JP;
Takao Arai, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A method and an apparatus for recording and reproducing a PCM audio signal either alone or together with a video signal, using a rotary-head type scanner. An analog audio signal is converted into a digital signal having a predetermined number of quantization bits in each predetermined sampling period. The digital signal is recorded on a recording medium such as a magnetic tape, and an analog audio signal is reproduced from the digital signal reproduced from the recording medium. In the reproducing mode, the signal reproduced from the tape is written into a memory where error detection, correction and deinterleaving are carried out, and the signal is then read from the memory and applied to a D/A converter. The write rate from the memory depends on the video field period, and the read rate depends on the sampling period. Accordingly, the difference between the write address and the read address of the memory depends on the difference between the field period and the sampling period. By changing a master clock, which defines the sampling period controlled by the read address, in accordance with the address difference, the difference between the video signal field period and the audio signal sampling period can be controlled and compensated.